You might put in the effort to provide the ability to simulate exactly when the MCU does things internally and externally, e.g. when it updates the data register in the serial port, when it accesses external resources, etc. It also would be useful to give your emulator the ability to handle additional serial ports, timers, etc, as well as handling their SFR's. There are so many "un-emulated" variants, a straightforward mechanism for emulating them would be really useful, as would a cycle counter and instruction timer that yields exact cycle counts between markers in the executed code. Making these calculations adaptable to one-clock, two-clock, four-clock types as well as the typical 12-clock MCU would be useful, too.

Just a thought. It's something the "others" don't do.

RE